1. Field of the Invention
The present invention relates to a composition for tires which provides a vehicle tire tread with low rolling resistance as well as high wet grip performance and more particularly to a tire tread provided with a balance among five major characteristic properties, tire rolling resistance, wet grip performance, wear resistance, steering stability and crack resistance.
2. Prior Art
In conventional tire treades styrene butadiene copolymers of the straight chain type obtained by emulsion polymerization were used in most cases, and those obtained by solution polymerization were also used. Also, in terms of the relationship between styrene content and vinyl content, the conventional styrene butadiene polymers were less in vinyl content (the vinyl conent here means, 1, 2-bonded butadiene content in the butadiene component) and furthermore were insufficient in the balancing among the above mentioned five major characteristics.